1. Field of the Invention
The present invention relates to a centering punch, and more particularly to a centering punch that can be centered and aligned easily and exactly.
2. Description of the Related Art
A conventional centering punch in accordance with the prior art shown in FIGS. 15–18 comprises a first body 80 having an inner wall having a first end formed with a receiving recess 803, a mediate portion formed with a tapered face 802 and a second end formed with a receiving chamber 801, a fixing member 83 mounted on the first end of the first body 80, a second body 87 having a first end mounted on the second end of the first body 80 and a second end formed with a passage 872 and having an inside formed with a receiving space 871, a punching head 81 movably mounted in the receiving recess 803 of the first body 80 and having a first end formed with a control hole 811, an elastic member 82 mounted in the receiving recess 803 of the first body 80 and urged between a second end of the punching head 81 and the fixing member 83, a first push member 86 movably mounted in the passage 872 of the second body 87 and having an enlarged first end 860 rested on a shoulder 875 formed between the receiving space 871 and the passage 872 of the second body 87 and a second end protruded outward from the passage 872 of the second body 87, a second push member 84 movably mounted in the receiving space 871 of the second body 87 and having a first end rested on the first end of the punching head 81 and located adjacent to the control hole 811 of the punching head 81 and an enlarged second end 840 rested on the enlarged first end 860 of the first push member 86, and a spring 85 mounted on the second push member 84 and urged between the enlarged second end 840 of the second push member 84 and the first end of the punching head 81.
As shown in FIG. 16, the second push member 84 is rested on the first end of the punching head 81 eccentrically by an elastic force of the spring 85, so that the first end of the second push member 84 is rested on the first end of the punching head 81 and is not in alignment with the control hole 811 of the punching head 81.
As shown in FIG. 17, the second end of the first push member 86 is provided with a socket (not shown) which is mounted on a tool (not shown), such as a nail or the like, which is moved to press a working face (not shown). When the first body 80 is held and driven by a user's one hand to move toward the working face, the first push member 86 is pushed by the reaction of the working face to move toward the punching head 81, so that the second push member 84 is driven to press and move the punching head 81 and to compress the elastic member 82. At this time, the spring 85 is compressed and guided by the tapered face 802 of the first body 80, so that the second push member 84 is moved radially in the receiving space 871 of the second body 87 by guidance of the tapered face 802 of the first body 80 until the first end of the second push member 84 is in alignment with the control hole 811 of the punching head 81.
As shown in FIG. 18, after the first end of the second push member 84 is in alignment with the control hole 811 of the punching head 81, the punching head 81 is driven by the restoring force of the elastic member 82 to hit the second push member 84 which hits the first push member 86, so that the first push member 86 is pushed outward to drive the tool to pierce the working face, thereby forming a hole (not shown) in the working face. At this time, the first end of the second push member 84 is inserted into the control hole 811 of the punching head 81.
However, the first end of the second push member 84 is not easily in alignment with the control hole 811 of the punching head 81, so that the conventional centering punch cannot be centered and aligned exactly, thereby limiting operation of the conventional centering punch.